simpledefaultlist.lzx

<library>
    <!--- A list class that handles a default value. 
          Input and output for the list is defined to be in this format:
          <code>
          <list name="fubar">
            <item text="foo" value="bar" default="true"/>
            <item text="goo" value="mar"/>
          </list>
          </code>
         
          Currently only works with dataoption="lazy" or "pooling"
    -->
    <class name="simpledefaultlist" extends="list">

        <!-- methods overridded from baseformitem -->
        <method name="rollback">

            if (this.changed) {
               // Replace the data with our archived copy
               // this will effectively reset our datapath
                this.datapath.p.parentNode.replaceChild(
                    this.rollbackvalue,
                    this.datapath.p );
                this.setAttribute('changed', false);
            }

        </method>
        
        <!-- simpledefaultlist attributes -->
        <!--- LzDataElement of the default node 
              null means the list has no default -->
        <attribute name="defaultitem" value="null"/>

        <!--- Set to true if the default item should be selected whenever
            data is received -->
        <attribute name="autoselectdefault" value="true"/> 

        <handler name="ondata" args="d">
         
            //Debug.write( "ondata event", d);


            this.handleDataChange();    
                
                    
         
        </handler>

        <!--- keywords @private -->
        <method name="handleDataChange">

            this.rollbackvalue = this.datapath.p.cloneNode(true); 
            // Find the default node in the data
            this.setAttribute("defaultitem", this.findDefault());

            if (this.autoselectdefault) this.selectDefault();

            this.setChanged(false);

        </method>

        <!--- Searches through the data to find a default item. 
              Called when data is read into the list
              @returns: lzDataElement default: dataelement for default
        -->
        <method name="findDefault">
         
            //Debug.write("finding default", this.data);
            if (this.datapath.p == null) return null;
            if (!this.datapath.p.hasChildNodes()) return null;
            var nodes = this.datapath.p.childNodes;
            var curnode;
            // search the data for default="true"
            for (var i = 0; i < nodes.length; i++) {
                curnode = nodes[i];
                
                if (curnode.attributes["default"] == "true") {
                    //Debug.write("Found default! ", curnode);
                    return curnode;
                }
            }
            // Didn't find it, return null
            return null;
        
        </method>

        <!--- Selects the default item -->
        <method name="selectDefault">
            this.selectByData(this.defaultitem)
        </method>

        <!--- Selects an item based on a dataelement
            @param LzDataElement data: node to select -->
        <method name="selectByData" args="data">
            var view;
            if(data) {
                view = this._selector.getItemByData(data);

                select(view); 

            }
            return view;
        </method>

        <!--- Returns an XML representation of the data in the list 
        format:
            
        -->
        <method name="toXML">
              

            if (this.datapath.p == null) return "undefined";
            
            return this.datapath.serialize();

        
        </method>

        <!--- Sets default item
            @param view item: list item to make default -->
        <method name="setDefault" args="item">
           // Move this to selection manager???
            this.setDefaultByData(item.data);
        </method>

        <!--- Sets default item
            @param LzDataElement item: node to make default -->
        <method name="setDefaultByData" args="item">
            if (item == this.defaultitem) return;

        
           // Set the dataflags
            if (this.defaultitem) {
                this.defaultitem.removeAttr("default");
            }
            

           this.setAttribute("defaultitem", item);
           //Debug.write("set default item to ", this.defaultitem);
           
            if (this.defaultitem) {
           this.defaultitem.setAttr("default", "true");
            }
            
            this.setAttribute("changed", true);
        </method>

        
        <!--- Should be called when an item has been modified. -->
        <method name="modify" args="node">
             this.setAttribute("changed", true); 
        </method>
    </class>
</library>
<!-- * X_LZ_COPYRIGHT_BEGIN ***************************************************
* Copyright 2006-2008 Laszlo Systems, Inc.  All Rights Reserved.              *
* Use is subject to license terms.                                            *
* X_LZ_COPYRIGHT_END ****************************************************** -->
<!-- @LZX_VERSION@                                                         -->